Burr-removing attachments for screw-slotting machines



March 13, 1956 .1. M. SCHAEFFER 2,737,669

BURR-REIMOVING ATTACHMENTS FOR SCREW-SLOTTING MACHINES Filed April 5, 1952 5 Sheets-Sheet 1 March 13, 1956 J. M. SCHAEFFER 2,737,669

BURR-REMOVING ATTACHMENTS FOR SCREW-SLOTTING MACHINES Filed April 5, 1952 5 Sheets-Sheet 2 March 13, 1956 J. M. SCHAEFFER 2,737,669

BURR-REMOVING ATTACHMENTS FOR SCREW-SLOTTING MACHINES Filed April 5, 1952 5 Sheets-Sheet 3 53 0 INVENTOR March 13, 1956 J. M. SCHAEFFER 2,737,669

BURR-REMOVING ATTACHMENTS FOR-SCREWSLOTTING MACHINES Filed April 5, 1952 5 Sheets-Sheet 4 A A M.) 77 M V INVENTOR ATTORNEYS March 13, 1956 5 J. M. SCHAEFFER 2,737,669

BURR-REMOVING ATTACHMENTS FOR SCREW-SLOTTING MACHINES Filed April 5, 1952 5 Sheets-Sheet 5 :NVENTOR 67 BY 5 W ATTORNEYS United States Patent BURR-REMOVING ATTACHMENTS "SCREW-SLOTTING' MACHINES JosephzM; 'Schaelfer, Waterbury, Conn.,' assignor ;to ,The Waterbury. Farrel Foundry and Machine Company, Waterbury, .Cnn., a. corporation ofv Connecticut Application April 5, 1952, Serial No. 2 80,-767 .13 Claims. (Cl..1 0-'6) Thisainvention relates to' screw-slotting machines. and .moreparticularly to devices .oftthis character known .as .high speed scre slotting machines in that the screws are .fed. continuously: .to :the machine and. are.-slo.tted 1 during .theirtravel therethrough. This enablesthe work to'.-be .carriedcon ata very rapid rate as contrasted with-another common type of slotting machines wherein the 1 blanks Jemainastationary in the machine 'duringv the slotting-operation. 1

..In..the .type of machine with which the present application is.concerned, the screws .are fed to a rotary dial and are .carried through themachine by this-dial. lhe .dialaishollow, and mounted eccentrically-withinthe .dial -is a central screw-slotting saw. AThesaw'rotateszin.aidi- .rection oppositethatofthe dial and duetodhe eccentricity ofthe two rotatingmembers the .spacebetweenithecutting edge of the saw and the..inner.peripheryof thegdialds such thatthe saw would not come incontact with the head ofalbla'nk carried bytheudial during a.large part.=of;-its .movement. .l-Iowever, thesaw will contact t he head of the .blank, during approximately .90. degrees ofits Itrayel. .It thus. effectively slotseach. ,screw and E moreover. :is in engagement with. anumber. of. blanks or screw-heads. at one 1 time so that there. is no. .abrupt.shift .or-change, over .from oneblank to another;

' 'The carrying. dialis, in the form .of a ringt'rneinbertpro- .vided with a plurality of radialgrooves-.upon..onesface to hold theshanks or bodies of theblanks. ibis-necessary .thaLthe blanks beheld .againstrotationAwhilegtlreyeere in.contact withihesaw. and also :that .they. .be;.pr;evented .frornf droppidgout of .thecarrying dial.:once the have beenentrained.therein. 1 Means are provided. for' this purpose .in the-form of av pressnreapad adjustably; mounted .in front .of the. carryingqdial so that th s? Pressure;v pad twill beaiigagainstathe shanks or. bodies .of.:the.;blanks-and hold ,the mnin placerin the .dial. a Also a..retaini aring is LSeCUld to -this pressure .pad to lie. radiallyainwardly eof .lthegcarriert :dial and engage the .prevent .them. frorn dropping out oftthe dial.

. inconnection with-the slotting ofsome typesg-ofgserews, a burr is left at the edge of the slot .formed;..,1n:.the;.:head ".Of thescrew and it is desirableto.:provide::ther.slotting :machine with a. trimmingsor deburring:cuttertorrmove it these. burrs. The present applicationldeals particularly with the provision of means for this function.

For this purpose an insert is set into the rear face of the pressure pad'at a'point inthe latterfollowing that portion thereof wherein the saw engages the blanks. {This insert is roughened or knurled'upon itsouter face soithat when the blanks in their travel about the was ff the carrier are engaged by the knurled surface, .ofi"the ns'ert, .they are caused to..rotate upon -their.axes.l red toj the pressure. pad ..at approximately the1 same.;circu:mterential position .as the, insertnjustldescribed .is. aLcutter so -arranged. ,that itengages the heads ofi-thescrews ;dl iring their. rotation to. ,trimaor. cut. the burrs therefrom.

. Que: .object. of the :present invention is; to: proiiidez; a

heads of theablanks to showing the burr-removing cutter in Zof gradial grooves 25 (:Fig. FWhiCh' grooves :are adapted;

new ;and;; improved high speed slottingmachine-for ithe .slotting'of -screw or bolt blanks orthe like.

...Another object of the invention is to provide a high 1speed,.screw-slotting machine having a continuously rotating carrying dial with improved means for removing the burrsfrom the slotted screw heads duringtheirmove- .ment ;through the machine by the carrier.

A still further'object of the invention is -to provide a high pspeed screw-slotting machinehaving a continuously .rotating carrying :dial for .the blanks with armember mounted upon a fixed point of .the machine with which ,=the blanks are caused to engage duringthe rotation of the carrier, this member having a knurled. :surface, to :ro- -tate=-the blanks when in engagement therewith and to pro- -vide a. cutter upon afixed part ,.of .themachine at -the proper position such that .theheads of the blanks will be rotated .;in engagement ,with the. cutting .means .to ;.remove .the burrs ther efrom.

-.A .stillhfurther object of the invention ,is the,;provision in a machine of the character described above of, asingle .cutter occupying a given stationin the travel. of the. blanks and, means for rotating ,the. blanks when opposite this .stationtso that...the cutter =will trim the burrs ,fro m v.t'he heads of the, blanks.

{.TQLthese and other. ends ,theinvention, consists. in "the ,novel. ,features...and. combinations of parts tobehereinafter described and ,claimed.

In the. accompanying .dt wing Fig. 1 is .a ,front eleyationalyiew ,of a portionof -a .s rs ct't amach neem ody ng ve tion;

TIF gL' '2..i a se tion l .vie .on line 22. of Fig. .1;

' FigL 3.jis a. detail sectional view on line 373 of. Rigel;

f F1g. 4 is asectional view on line 4 4 of Fig. 3;

"Fig; 5' is an elevational view of a portion of the rear face ofthe pressure pad on line 5 5 of Fig.3;

Fig.' 6.is. a top view of a trimming onburr-l' noltin .cutter; V I

, Fig. 7 is a front view of, a screw-slotting machine embodying a modified form of myinvention;

Fig.8 is .a perspective view ofjthe 5 insert or block having serrationsthereon to engage and turn the blank du1 i ng the burr-removing operation; Fig; 9 is an enlarged top plan view of a portion ofthe block shown in'Fig. 8;

}Fig." 10 is anenla ged sectional view on line 10- pf Fig.7;

' Fig. 11 is a view of thepressure ofmy inyention'shownin Fig. 7; lfig'. 12 is a sectional view on line 12 12 of liig. 10

' n a m t'w hth pad usedin the form wo'rk'; Fig. -13 is a view similar toFig, 11 showing a pressure -pad ofmodified form; and i: Fig. 14 is a'top view of the cutter. i

fTo illustrate a preferred embodiment of my invention, I have shown in the drawings 'a' screw-slotting machine having a stationary head '10 (Fig; '2) to which is secured abea'ring sleeve 11 by-bolts 12. Within the bearing sleeve is'rotatably mounted the shaft 1'3 -upon'the forwardend 'of which is secured the-saw or cutter l lby retaining ring adjacentflthe the clamping members 15 and16 and 'nut 17. 'f The he'ad '10 is a ring-like member and rotatably mounted-Within the headisthe'la 'ub 18 of a gear 19,"the l'lub being carried upon anti-friction;bearings"20 and 21 so that the-gear will be freely rotatable independently "Ihe carrier dial 23 issecured tothe'forward face 'of the gear-"ISF -by-p'ins 24 and-screws"24 This carn'er dial comprises an annular member having a plurality 1)"cutfint'o its forward face, as shown in this figure and also in Fig. 2, to receive the bodies of the blanks 26 with the heads of the blanks directed inwardly or toward the radius of the carrier dial.

From Fig. 2 of the drawings it will be apparent that while the shaft 13 is mounted in the bearing sleeve 11, the carrier dial which is secured to the gear 19 is mounted in an opening in the stationary head by the ball bearings 20 and 21. The opening in the head which receives the bearings is slightly eccentric to the axis of the shaft 13 so that, as shown in Fig. 1, the saw 14 will be eccentrically mounted with respect to the inner periphery of the carrier dial 23. From inspection of this figure, it will be seen that at the righthand side of the figure the teeth of the cutter approach the inner periphery of the carrier ring more closely than at the lefthand side of the figure and, as shown in dotted lines at the right, the teeth of the cutter will engage the heads of blanks 26 for approximately 90 degrees of their travel about the axis of the cutter. It is also preferable to rotate the cutter in a direction opposite to the direction of rotation of. the carrier dial, and means, not shown, are provided to effect rotation of these parts in opposite directions.

Blanks may be delivered to the machine by a chute between spaced members 27 and 28 (Fig. 2) and, as also shown in Fig. 1, this chute may be provided with a cover plate 29 to prevent the blanks being dislodged from the chute, the blanks traveling along the chute with their heads upwardly between the cover plate and the members 27 and 28. When the blanks reach the end of this chute they are picked up by an indexing wheel 31 mounted on a vertical shaft 32 and rotated by any suitable means, not shown. This wheel carries the blanks through an arc of approximately 180 degrees from the chute to the carrier wheel 23 (Fig. 2) where they are picked up by the latter and carried about the periphery of the saw.

It is, of course, necessary to provide some means to prevent blanks from becoming dislodged from the grooves of the carrier wheel 23, and also to hold them in place with sufficient pressure so that they will be properly operated upon by the cutter 14, and the means for effecting this result will now be described.

As shown in Fig. 2, a cover plate 35 is secured to the face of the stationary head 10 by screws 36, this cover plate being a ring-like member extending through an angle of substantially 270 degrees, one edge of it being shown at 37 and the opposite edge being shown at 38. As shown in Fig. 2, the opening in this member is of greater diameter than the carrier dial 23.

Mounted within this opening in the cover plate 35 is a pressure pad 40 of arcuate shape and of substantially three quarters of a circle in extent, this pad being held in place by its engagement with the inner circumference of the cover plate and being held against rotation by a key 41 (Fig. 2) secured by a screw 42 to the cover plate. The lower edge of this key enters a recess 43 in the pressure pad so as to permit the latter to move toward and from the carrier dial 23 or axially of the shaft 13 while preventing it from rotating.

Secured to the inner periphery of the pressure pad by screws 45 is a retainer ring 46 having at its inner edge a flange 47 which lies against the head of the blank and holds it in one of the grooves in the carrier dial. The grooves in the carrier dial are preferably somewhat shallower than the diameters of the bodies of the blanks so that the latter project slightly from the surface of the dial, and it will be seen from Fig. 2 that the inner edge of the pressure pad 40 bears against the bodies of the blanks and holds them against rotation while the retainer ring 46 holds them against movement in a direction radially of the carrier.

It is necessary to apply pressure to the pressure pad in order to cause the inner surface thereof to bear against .block or insert can be adjusted the blanks, and this is effected by means of a spring plate 50 shown in Fig. 1. This plate is secured to the cover plate 35 by screws 51 and is slotted, as shown at 52 and 53, to provide resilient fingers 54, the inner ends of which extend radially to a position opposite the pressure pad 40. It will be seen from Fig. 1 of the drawings that this spring plate is of slightly less extent circumferentially than either the pressure pad 40 or the cover plate 35.

Adjusting screws 55 are threaded in the spring fingers 54 adjacent the inner ends thereof, which screws bear against the pressure pad 40 to urge the latter inwardly against the blanks. It will be understood that as the fingers 54 are resilient, the pressure upon the pad may be varied by the threaded adjustment of the screws 55, and as there are a number of these fingers, the pressure at one point may be varied with respect to that at another point. For example, the large opening 53 in the spring plate 50 is provided to permit the mounting of a bracket 56 (Fig. 1) to support a cutter for trimming the burrs from the blanks. At this point it is desirable to decrease the pressure so that the blanks may rotate and, with the independent spring fingers 54, each having an adjusting screw at its inner end bearing against the pressure pad, this adjustment may be readily effected.

The bracket 56, shown more particularly in Fig. 3, is secured by screws 57 to the face of the pressure pad 40 at the zone of the latter where the heads of the blanks are no longer engaged by the slotting saw. To the lower surface of the bracket is secured a cutter blade 58 having a cutting edge 59 thereon. The edge 59 may be of any desired form depending upon the shape of the head of the screw so that, it will properly engage this head and remove the burr therefrom.

As shown in Fig. 3, the cutter is secured to the bracket 56 by the screw 60 which is received in an elongated or enlarged slot 61 so that the cutter blade may be adjusted toward and from the carrier dial 23 in order that the cutting edge will have proper engagement with the head of the blank. It will, of course, be understood that as the cutter is mounted upon the pressure pad, it will be resiliently urged toward the carrier dial by the spring fingers 54 which urge the pressure pad inwardly.

Upon the rear face of the pressure pad at a position substantially opposite the bracket 56 and cutter 58, a recess 62 is provided, and in this recess is seated an insert 63, the outer face of which is knurled or roughened, as shown in Fig. 5, the insert being secured in place by the screws 64. This insert is of arcuate shape and the roughened surface thereof will engage the shanks of the blanks, and the latter are carried past the insert by the carrier dial, thus effecting rotation of the blanks with the heads thereof in engagement with the edge 59. It will also be understood that the cutter blade 58 is of arcuate shape in cross section so that it will fit closely against the inner periphery of the pressure pad 40, the body of the blade lying in a recess in the outer surface of the retaining ring 46.

In the form of my invention previously described the knurled insert 63 (Fig. 5) which engages and rotates the blanks during the deburring operation is secured fixedly to the pressure pad 40, and, therefore, moves in and out with this pressure pad toward and from the carrier dial as adjusted by the screws 55. In some cases where there is a variation in the diameters of the blanks, it may be desirable to provide a separate block or insert, the position of which may be varied relatively to the pressure pad 40, this block being serrated to rotate the blanks and engaging them adjacent the burr-removing cutter. Also in this event it may be desirable to form the spring plate (the plate 50 of Fig. 1) in two or more sections so as to provide a separate section of the spring plate to bear against the insert or block which is slidably mounted in the pressure pad so that the spring pressure upon this entirely independently of 5 =2 the spring pressure applied to theremainder of. the presthe. properpoint on the blank as the latter isca1 ried over .Sure;pad. v its arcuate. path. "The form fof'th e blade-may, ofcourse, Such a constructionis'shc'ivn in Figsf7 to TB of the vary depending upon the shape-of the head of the screw drawings, and the burr-removing cutter shownin these which is being .slotted. As shownjthe cutterfis beveled figures is also of a form'somewhat clifferent than ft h at 5 at 86 to match the bevel of thehead of a flat. head screw. described above. -As illustrated in Fig. IOthe' head of Upon the .upper side of the cutter is provided aclearance the slotting device is shown at .10 towhich-issecured a angle 37 leaving an arcuate cuttingedge which will envcover: plate 35 similar to that previously described Also gagedhe blank at the proper point during its revolution -mounted within the opening of this cover plate :is. a ltoremovelthe burr at theend of theslot. As shown in pressure pad 64 of the formshown in Fig. 11;the pad "EigQIZ, the edge ofthe cutter is substantially parallel being of arcuate form and comprising an arc bfsub stan with the face of this dial. The contour of the edge 'ofjthe y 270 grees. cutter will, of course, be-suited totheshape ofthe head .Secured to the cover plate 35, as shown-moreespecialof the screw being operated upon. 1y n Fig. 7, i h pring pl e 65 which, as will benot'ed, in thejevent' that the edge of the 'cutter does notjli'ne .is of less extent than the. plate 50 shown in Big. 1. ThiS up with the burr to be removed from the screw h'eadfthe plate is slotted, as shown at 66, so as to ,provide vrec'utte 14 may be adjustedso as to cutadeeper orshallower fsilient fingers 67, and adjusting screws 68- are threaded o v i the head of the screw"which will, of'eourse, Iihtothese fingers h s t e-p s P tO Inake a corresponding difference .in the position of the ur thelatterytewerdthe =c ju en burr. Considerable tolerance is permitted." in the depth pf {of thescrews will, Of' course, y- Pressure. e rte ;the screw slot so that when a :cuttenis employed having y the Pressure P p n the hlhnksthe/ contour required by the shape or the head, thejedge --A spring plate sectiOn69-0f the s mef rms jp .offthejcutter will be at thep'roperi point to removefthe 65 .but 'formed separately therefrornis also,.secured to b f i h head ofthe. screw.

'ethe e0VeT'P1ate35hy 1 -t In some instances Where long screws are being treated,

P s f smaller area than .the pla "65 asfit Q fly-OP- .the, threads will not extend all the way to the head of the efates during that Portion of the travel 0f h h screw. in this event it'is undesirable to have the serra- 'ing which the burr is removed. -An .adjusting screw "71 g g 75. a th blankadjacent the head as any marks s mounted in the inner end fthe Plate ihh left byjthese knurlings or serrations would not be removed -1 Will he noted from 1 g- 11 h t -th ;;;P jjduring the. threading operation. When' such screwsarejto tsurepad 64 is provided with a. cut-out portion. or .30 be slotted; I employ the pressure pad 64 shown in Fig'. 13 r 72 and in h recess fl y m e' wa wherein the recessor cut-out portion 72 is provided upon tins rt 0r l k 3 Which y mOVe t ie -Hem @tjhe outer circumference of this pad insteadof'upon its h rri r l n p n yf t p e s pa 'jin'nfer; circumference. 'The insert .or block 73 is'slidably l k n r flth m mb 73 i adaptfcd o b S fnoufnted in the'recess 72?".as describedin connection with contacted by the inner end of the adjusting screw"7 1 so .35 t-h prejsflsurelpad 64h shown i Fi 11, d th b cking as to adjust the pressure of the insert on theblank. 1 On -mb f'm u th i ert 73 wi11 be e g g d by the the-inn r fa e f t e-i 7 a p e memb screw 71 as before. However, when 'long blanks are 75 carrying serrations 76 PQh its illheif h e f being slotted and the insert is placedat 72 in the pressure ShOWh in g- 10, the blank M e' ylh pad? 64 it is necessary to move the spring plate 69 serrations and caused to rotate Within the"r' c 140 radially outwardly. It will benoted from Fig 7 that the grooves of the carrier dial 23. The le'ngtlforthe xtent cover plate i provided withopgnings 90 disposed *ofthe serrated portion 76 which e'ng'a'gesthe blank -is w'gffdly'f 'the osifio f the'screws 70 Tl- 1 3169 Suhieieht only to g g one blank titihleisotfthat jmjay'jbefrnoved outwardly so that the screws 70 will enter the' blanks always be positively rotated. Qther'Wise, the this result in crew being V0 blanks were. engaged the meml'SerrflSiFat the "disp'os ed"at the'prop'er radial distance center of am t m and hhe waseslightly larger in diameteli-thah the pressure padto engage the block 74 when the latter is the other, the'larger one-would control: and thesmaller in thecreggss 72a one'would not be rotatedand, therefore;wouldnnot have \ivhil I h ho nd d scribed some preferred "the burr removed- It may' f n vcnien e v 'bodinrents of myinvention, it will be understood that it is t f of h member h t c s n- 'not te belimited to'all of.the details shown; but is capable -s ry and f h entire 1 n e e r a i ofmo'dification'and variation within the'spirit of the inven- --n 1ay be cut back,- :as shown at 77, or -the portion of.',t h e tipn and within the scopeof the claims. blotck left smooth at this point so thatthe blank would lrclarimis: I n y. be engaged y the errations 76. and th e m 1.11 a 'screw slottingiimaohine, a' rotatabl mounted Q y a S-Ufiieieht movement of these n f g sa carrier .comp'rising a ring-like mernber having radial one blank at atime inthe rotation of the carrier fdial. igroovesrinlitsfacelo receive uthekblanks, a slotting cutter I 1 hi Of y invention P Y a retainer rotatably mounted within the carrier, theaxis of the cutter ring 46 Similar to that Shown in b v "being eccentric'to that of the carrier, means for rotating cutter-80 is secured t this 'r in r g y. Screw the cutter and carrier, means forretaining the blanks in -and it Will be noted p h e iszflimtheiletaiher said grooves during rotation of the carrier, a trimming through Which the'serew PasseS is'shghtly larger cutternon-rota'tably mounted on the-machine in spaced "t the y of the Screws) 'thattthe Cutter sotmay'be relationto the faceofflthe carrier .past which-cutter the adjusted toward-and'frorn'thecarrier dial and theiblanks blanks are carried b the ie aft engagement w therein. the slotting cutter -and relatively stationary. meanslfor 3 The form'of cutt r i h0W if! Figsi lotahd iahd'it rotating said blanks on their axes as they are carried past =will be seen that it is a 'double ended cutter having'fcut- 1 said trimming cutter trim the burrs th f f sgid g edges 83 84 end it is also :PIeVided: W w trimming cutting being disposed on the side oftheblanks openings 85 :for :the screw i81-so that thecutter may be pppositethe carrien xreversedin position andi-aeither dg qemp y t f 2. In a screw-slotting machine, a rotatablymounted 'cutting'edge. A's;shoWn-inFig-7,;the;-cutter-is of-arcucarrier comprising a ring-like. membermhaving radial ateshape in cross-section ;so as to fit snugly within the' grooves in itsface to receive the blanks, aslottingcutter retainer: ring 46- which is of arcuate -form'-;and against .rotatably mounted withinthe carrier,theaxispfitheeutter r t-he insert 73,:the lower surface of which: is also of arcuate beingeccentric to that of thecarrier, means forrotatingthe -form. 1 The cutter-maybe provided with a planeedge, ,cutter and-carrien means for retainingtheblanks in said as shown, the edge being of arcuate form so as to engage ..groovesduring-rotation of theparrier, a trimtning cutter non-rotatably mounted on the machine in spaced relation to the face of the carrier past which cutter the blanks are carried by the carrier after engagement with the slotting cutter, and relatively stationary means for rotating said blanks on their axes as they are carried past said trimming cutter to trim the burrs therefrom, said trimming cutter being disposed on the side of the blanks opposite the carrier and being adjustable toward and from the carrier dial.

3. In a screw-slotting machine, a rotatably mounted carrier comprising a ring-like member having radial grooves in its face to receive the blanks, retaining means for retaining the blanks in said grooves, a slotting cutter rotatably mounted within the carrier, the axis of the cutter being eccentric to that of the carrier, means for rotating the cutter and carrier, a trimming cutter non-rotatably mounted on the machine past which the blanks are carried by the carrier after engagement with the slotting cutter, means for rotating said blanks on their axes as they are carried past said trimming cutter by the carrier to trim the burrs therefrom, said rotating means comprising a knurled member non-rotatably mounted on the machine in position to engage a part of the blanks as they are carried past said member by the carrier dial, and spring means for urging said rotating means toward the blanks.

4. In a screw-slotting machine, a rotatably mounted carrier comprising a ring-like member having radial grooves in its face to receive the blanks, a slotting cutter rotatably mounted within the carrier, the axis of the cutter being eccentric to that of the carrier, means for rotating the cutter and carrier, a pressure member non-rotatably mounted opposite the face of the carrier to engage the bodies of the blanks and hold them in place, a trimming cutter mounted on said pressure member in position to engage the heads of the blanks as they are carried around by the carrier after being slotted by the slotting cutter, and means to rotate the blanks as they are carried past the trimming cutter.

5. In a screw-slotting machine, a rotatably mounted carrier comprising a ring-like member having radial grooves in its face to receive the blanks, a slotting cutter rotatably mounted within the carrier, the axis of the cutter being eccentric to that of the carrier, means for rotating the cutter and carrier, at pressure member non-rotatably mounted opposite the face of the carrier to engage the bodies of the blanks and hold them in place, a trimming cutter mounted on said pressure member to engage the heads of the blanks as they are carried around by the carrier after being slotted by the slotting cutter, and means to rotate the blanks as they are carried past the trimming cutter, said rotating means being mounted on the pressure member.

6. In a screw-slotting machine, a rotatably mounted carrier comprising a ring-like member having radial grooves in its face to receive the blanks, a slotting cutter rotatably mounted within the carrier, the axis of the cutter being eccentric to that of the carrier, means for rotating the cutter and carrier, a pressure member non-rotatably mounted opposite the face of the carrier to engage the bodies of the blanks and hold them in place, a trimming cutter mounted on said pressure member to engage the heads of the blanks as they are carried around by the carrier after being slotted by the slotting cutter, means to rotate the blanks as they are carried past the trimming cutter, and said trimming cutter being adjustable toward and from the carrier relatively to the pressure member.

7. In a screw-slotting machine, a rotatably mounted carrier comprising a ring-like member having radial grooves in its face to receive the blanks, a slotting cutter rotatably mounted within the carrier, the axis of the cutter being eccentric to that of the carrier, means for rotating the cutter and carrier, a pressure member non-rotatably mounted opposite the face of the carrier to engage the bodies of the blanks and hold them in place, a trimming cutter to engage the heads of the blanks as they are carried around by the carrier after being slotted by the slot- 8 ting cutter, means to rotate the blanks when in engagement with said trimming cutter, said rotating means and said trimming cutter both being carried by said pressure member, and spring means urging said pressure member toward the carrier.

8. A screw-slotting machine comprising a head, a ringshaped carrier rotatably mounted in the head having means to receive the headed blanks and carry them in a circular path with their axes disposed substantially radially of the dial, a pressure pad supported by the head in opposed spaced relation to the carrier to engage the shanks of the blanks and hold them in said carrier, means mounting said pressure pad for movement toward and from the carrier, a member attached to said pressure pad for movement toward and from the carrier independently of said pressure pad, said member having means to engage the blanks and rotate them on their axes, and cutting means supported from the head on the side of the blanks opposite the carrier to trim the blanks while they are rotated by said member, and carried past said cutting means by the carrier.

9. A screw-slotting machine comprising a head, a ringshaped carrier rotatably mounted in the head having means to receive the headed blanks and carry them in a circular path with their axes disposed substantially radially of the dial, a pressure pad supported by the head in opposed spaced relation to the carrier to engage the shanks of the blanks and hold them in said carrier, means mounting said pressure pad for movement toward and from the carrier, a member attached to said pressure pad for movement toward and from the carrier, a member attached to said pressure pad for movement toward and from the carrier independently of said pressure pad, said member having means to engage the shanks of the blanks and rotate them on their axes, and cutting means to engage and trim the heads of the blanks while being rotated by said member, said cutting means being adjustably secured to said pressure pad.

10. A screw-slotting machine comprising ahead, a ringshaped carrier rotatably mounted in the head having means to receive the headed blanks and carry them in a circular path with their axes disposed substantially radially of the dial, a pressure pad supported by the head in opposed spaced relation to the carrier to engage the shanks of the blanks and hold them in said carrier, means mounting said pressure pad for movement toward and from the carrier, a member attached to said pressure pad for movement toward and from the carrier independently of said pressure pad, said member having means to engage the shanks of the blanks and rotate them on their axes, cutting means to engage and trim the heads of the blanks while being rotated by said member, said cutting means comprising a blade having a cutting edge on each end thereof, and said blade being securable in reversed positions on said pressure pad to direct either of said edges toward the work.

11. A screw-slotting machine having a stationary head, a ring-shaped carrier dial rotatably supported thereby for carrying the blanks in a circular path, and a rotating slotting cutter mounted eccentrically within said dial to engage and slot the screw blanks at one portion of their travel over said path, an arcuate member nonrotatably mounted on the head in opposed spaced relation to the dial to engage the bodies of the blanks and hold them in place in the dial, means on said member to effect rotation of the blanks in the dial at a following point in said path after they have been engaged by the slotting cutter, and nonrotatably mounted means to trim the burrs from the blanks as they are rotated in the dial and carried past said trimming means by rotation of the dial.

12. A screw-slotting machine as in claim 11 wherein said trimming means is mounted upon said arcuate member.

13. A screw-slotting machine as in claim 11 wherein said trimming means is mounted upon said arcuate memher, and the latter is spring-urged toward the dial.

References Cited in the file of this patent UNITED STATES PATENTS 223,730 Harvey Jan. 20, 1880 1,296,154 Atchison Mar. 4, 1919 1,977,556 Hogue Oct. 16, 1934 

